Before her death in 2015, Mrs Maynard had been told she was to attend the inquest as a witness and had met with lawyers engaged by Queensland Nurses' Union.

Mr Lock said that in a September 29, 2015, letter to counsel assisting the Mickelo inquest, Ms Maynard had written: "I now have been told they are gunning for me," adding, "I am sorry but am unable to take the stress of trying to answer any more."

She also sent or left letters for her lawyers, daughter and husband indicating giving evidence at the inquest was a significant stressor.

Inmates in an exercise yard at Woodford Correctional Centre

She was concerned that she was the only member of the prison's nursing staff who was being called to give evidence.

"It is probable she had formed a view she was being blamed for the death, and her clinical judgment as a nurse was under scrutiny," Mr Lock said.

Mr Lock said in his inquest decision regarding the death of Mr Mickelo he made no adverse findings about Mrs Maynard's actions concerning his care.

Mr Lock found there had been some considerable planning for the potential for Mrs Maynard's overdose for weeks or longer.

He said it was likely the final decision was only made after she wrote letters on September 23 and 24, 2015, although she did not express any suicidal thoughts in them.

The inquest heard before her death Mrs Maynard researched and spoke to colleagues about euthanasia and also changed her will.

Mr Lock said Mrs Maynard attended counselling sessions provided by her employer in the lead up to her death but her counsellor and GP saw no evidence of suicidal ideation.

There was a high possibility that Mrs Maynard accessed the insulin from the prison medical unit, Mr Lock said.

No insulin was found in the hotel room where Mrs Maynard was found unconscious, but a doctor said she could have disposed of it before feeling the insulin effects.

Mr Lock criticised a police officer for failing to search a garbage area and for failing to check hotel CCTV footage to see if she left the room.

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